1. Field of the Invention
The present invention relates to a winged craft using a ground-surface-effect so as to exhibit a capability intermediate that of a ship and an airplane so as to be capable of gliding above a water surface or a ground surface.
2. Description of the Prior Art
A ground-surface-effect winged craft representative of those in the prior art is illustrated in FIG. 4.
The ground-surface-effect winged craft is designed, as is generally known, such that it can fly closely to the water or the ground by bringing about a condition in which pressure of an airflow along the lower surface of a wing is produced by the ground-surface-effect caused when the craft approaches the surface of the ground or water to thereby generate lift.
As shown in FIG. 4, the ground-surface-effect winged craft in the prior art has a configuration similar to an airplane, in which a main body 51 is formed as a fuselage, a wing 52 is formed as a main wing, and the plane has conventional horizontal 55 and vertical 56 tails.
In order to enhance the ground-surface-effect, for a given main body 51, a Lippisch wing is employed as the wing 52, and at the ends of the wing are equipped floats 53 and V-shaped direction-stabilizer planes 54, the area of the wing being larger than that of the conventional airplane.
Consequently, in contrast to the fact that an air speed is said to be generally about 100 km/hr in the case of a light plane such as Cessna plane, it is reduced to 50-60 km/hr in the case of the subject winged craft.
However, the above-described ground-surface-effect winged craft in the prior art gives rise to the following problems to be resolved.
That is, the above-mentioned type of ground-surface-effect winged craft in the prior art has disadvantages in that it is hard to turn because upon banking the float 53 comes into contact with the water and in that its lateral stability is poor.
Furthermore, regarding the ground-surface-effect per se produced by the winged craft, the clearance between the wing and the ground is about 1/10.times.chord length (wing span), and if the left and right wings are subjected to waves in an irregular manner when the plane glides, for instance, above the water surface, then the possibility of the balance of the craft being broken is very high.
Especially, there is a problem in that a water wave drag, a water wave impact or the like upon the floats 53 provided at the opposite ends of the wing 52 may influence take-off from the water surface and alighting on the water surface.